Dispenser and applicator for liquid weed exterminators



SeIPL 14, 1954 R. J. LUNN ET AL 2,689,068

DISPENSER AND APPLICATOR FOR LIQUID WEED EXTERMINATORS Filed Feb. 5, 1951 :inventors aef JL Gttornegs n'AF 4 Patented Sept. 14, 1954 ArtNr-ortica DISPENSER AND APPLICATOR FDR. LIQUID. WEED EXTERMINATORS' Robert J'. Lumi and Wilfred-W..Lowther, Stw Paul,

Minn., assigner-s to Donaldson` Company, Inem St. Paul, Minn.,y a corporationl of Delaware Application Februar-yf 5, 1951', Serial' N o. I209;381'

(Cl. 22E-321) y i Claims.

Our invent-ion; relates,` to improvements in de,- vices forI dispensing weedY exterminating: liqulds.: and applying the same to undesirable lawn weeds,

particularly those of the. broad leaf variety such as dandelion, plantain, chickweedr` and.l the. like. l

It is: anA established, fact, that; such lawn weedsl can,` very eiectively be controlledv by application thereto of; the chemical 234-13, dichlorophenoxyacetic acid., In; controlled solution, this chemicalis. a growth stimulant, but in'Y greater concentration, it causessuchrapid growth that the plant. root, system bursts. and the plant dies. For effecu tive extermination, this chemical is mixed with Water and, appliedl directly to the leaf surfacesy ofthe lawnweeds. Actually, the chemical 2,/l,D inA sufficientlyi concentrated; solutionto kill unde-- sirablev broad leaf Weed plants, will also destroy most anyr other plants or grass with which; it comes in; contact, and as al consequence, effec,- tive; control; of; undesirable weed; plants requires, localized; or controlled application.`

YInview of theA above, it is an object of ther inventionto provide an: improved device ,ofA the class; described whereby accurately controlled measured quantities of` Weed-destroying liquid-I may be locally applied., quickly andi easily, to undesirable lawny weeds or plants withv a, minimum of injury to desirable plantlife, such as domestic grass, clover andthe like.

Another important object` of the invention is the provision of; a device of they class described, involvinga liquid reservoir for storage ot. the weed exterminating liquid or the like and appump mechanism for controlled dispensingof the liquid, ofi an improved construction whereby leakage or seepageY of the stored liquid, during idler periodsl of the device,4 is eliminated; In this, connection, itmay be saidthat, our invention provides simple, and; eiiective; means; whereby the liquid reservoir ofi the deviceisautomatically sealed. against leakage or seepage of the contained liquid during` idle periods of thedevice, sothat a, relatively large quantity of a suitable weed exterminating liquid orthe like maybestoredl in the devicefor long periods without loss. f

Anotherimpor-tant objective or the invention is` the provision ofv simple and inexpensive means for#accomplishing--v theV important objective, last above notedf, without resorting to costly: closeworkingftolerances ofI the movable parts.

@ther objectives of'the invention are thel provision ofa device ofy the class described, which is highlyV efiicientinoperation, is very convenient to use, has a minimum of par-ts; has exceptionallyl longdife and can be producedL ata verylowcost;

The above and otherV highlyimportant obiects and: advantages of the invention will be madev apparentirom the following specification, claims and appended drawing;

Ay divisioni` of,` this application. was iiled by us; on*` February 15"-, 1952, under Seriali-No; 27330272'.

In. the accompanyingy drawing; like characters indicate. like, parts;

Referring to thedrawings:y

Fig; 1 is ai view. in. side4 elevation, with` Somer parts inl section and someparts broken away, of a preferred form. of; the; invention; and

Fig.. 2 is alsov a. View` in:y side elevationf, with` somey parts; broken, away; butv illustrating ay somev what'` modified form: of: the invention;k

Descrimionof Fic. 1.

The main-body offthedevice-of Fig: l'i's i`n the'- nat-ure-v off an elongated; cylinder, indicated asl an entirety by l. Preferably' and' as shown,Y this tubularfbody l comprisesv an elongated tubular shell 2- that is normally closed at its upper`- end by a readily displaceable cap 3 and at` its lower1 end by a supplemental body section 4, whichv its;r rigidly anchored to thesection- 2fA by screw threads' or the like, as shownat 51. The axial boreof the'- elongatedf tubular sect-ion 2' ory thevbod-'y l serves' as a reservoir 6l for Weedl exterminating liquidi,y such, for example, as 234-13; dichl'orophenoxyacetic acid, which' mayy be supplied through* the upper endofthe body I upon removal ot the-displaceable cap 31 Preferably, and; as shown, the= di'splaceablel cap section 3 is in the nature of'an` invertedcup offsyntheticrubberor-the like, which is telescopically appliedover the otherwiseV open'-,y

end ofthe section 2i and is. displaceabl'y'y locked in position by means of a spring Wire'ba'il l thei trunnionelikeends 8x of`l whichV pass through aligned apertures in theA capl 3f anditheupper` end ofthe tubular bodyi section 21. Thebail'fl serves asa convenient' meansfor hang-ing the device' and is merely spread sufficiently to withdrawthei inturned ends 8i thereoffrom the tubular4 body l to allow displacement or applicationof thecap section-3 '.y

The supplemental body vsection 4; has an axiall bore 9, which serves asa pump; cylinder and' isY closed at its outer end; and; hask its inner end" in: receiving communicationA with the axially' aligned bore lo the-bodysection 2:` The'closed' bottom end ofv` the supplemental bodyA section, 4' ispro'- vided'l with an axial plunger yborelili-which' i'szoff i the bore Hlv and* carries at its-inner' end* an ex'- panded head I2, which serves as, and may be hereinafter referred to as, a pump piston. The pump piston I2 has normal free working clearance with the cylinder bore 9 and is normally yieldingly urged or biased downwardly to the extreme lower position shown in Fig. 1 by means of a coil compression spring I3 having one end seated against the piston I2 and its other or upper end seated against an inturned ange or shoulder I4 of the body section 4. f

In this embodiment of the invention, the piston I2 is provided with a circumferentially-spaced series of restricted flow passages or apertures I5 extending therethrough to provide communication between the spaces above and below the piston I2, the lower ends of these passages I5 being disposed radially outwardly of the plunger II. A resilient annular valve element I6 is disposed immediately adjacent the undersurface of the piston I2 and is xedly secured on the plunger II so as to move therewith and the piston I2. It will be understood, however, that this resilient valve element I6 is free of the piston I2 so that it is free to flex upwardly and downwardly with respect thereto. In the preferred embodiment of the invention illustrated,` the resilient valve element I6 is in the nature of an axially perforated disc of rubber, synthetic rubber or the like, and is held or secured fast on the plunger II by friction engagement therewith through its own resilience or elasticity. In other words, the central aperture or perforation of the resilient flexible and elastic valve element I6 is of less diameter than the plunger II, so that a slight stretching of said valve element I6 is required to apply the same onto the plunger.

, The upper end portion of the plunger II is provided with a central axial discharge bore I'I, which is closed at its upper end at I8 and communicates at its lower end with a circumferentially-spaced series of downwardly and outwardly directed final discharge `orifices I9. The upper end portion of the axial flow orifice discharge passage I'I communicates with a circumferentially-spaced series of radial fluid intake passages 20, which, when the piston I2 is in its normal extreme lower position shown, open into the upper end'portion of plunger bore II! just below the plane of the resilient valve element I6.

With this arrangement, upward movements of the plunger II and piston I2 will be limited to a position wherein the discharge ends of the downwardly and outwardly directed final discharge passages I9v are closed. by being withdrawn slightly into the lower end'of the plunger bore I0. Hence, with this arrangement, the cylinder space below the piston I2 and yielding valve seal I6 will be automatically closed against downward discharge during periods when 'the' piston I2 is in its extreme upper positions, so that there will be no appreciable loss of fluid under these conditions. l i

Operation of Fig. 1

I When the piston I2 and plunger I I are in their normal extended positions of Fig. 1, the resilient valve element I6 is compressed between the piston I2 and the closed end of the body section 4 and serves as a yielding valve seal completely cutting off passage of fluid through the piston passages or orifices I5. Obviously then, in this position of the parts, there can be no seepage of fluid from the reservoir 6. The operator carries the device much like a Walking stick or cane. When he lcomes onto an undesirable weed or 4 plant in a lawn or the like, he places the end of the plunger II over the stem or center portion of that plant and then exerts sufficient pressure the downward pressure on the tubular body I and permit the plunger-equipped piston I2 to be returned to its normal bottom position under the yielding action of spring I3. During this return or relative downward movement of the piston I2, with respect to the tubular body I, the pres. sure below the resilient valve element I6, which now acts as a flap valve, will be greater thanthe pressure thereabove and will cause the said ap valve IB to be pressed against the bottom of piston I2 and close off the passages I5, causing fluid to be ejected through the flow passages 2B,

I'I and I9. The fluid discharged from the downwardly and outwardly-directed circumferentially-spaced passages or orices I9 will issue forthA as a spray from each said orifice I9 to collectively produce a circular spray pattern concentric with the axis of plunger II. The overall spray pattern thus produced will be of suiiicient over-` all diameter to assume ample wetting of the' selected plane or weed to assure destruction thereof, but will be suiiciently confined to pre-l vent material damage to the associated lawn grass, clover or the like. Of course, when the piston I2 again reaches its bottom extended position of the drawings, the valve disc I6 will again be compressed between the piston and the end of the cylinder 9 to completely isolate the reservoir 6 from the discharge orifices or passages 29. (In the device illustrated, no special means of venting the reservoir 6 to atmosphere has been i shown, sinceL it is assumed that there will be suilicient air leakage past the cap 3 to amply Vent the reservoir to atmosphere.)

The device illustrated in Fig. 1 may be made of any suitable metal or plastic material, but was particularly designed for fabrication for metal.

Description of Fig. 2

The modified device of Fig. 2 may also be made from any suitable material, but was particularly designed for fabrication largely from plastic parts, which may be inexpensively produced and is not subject to attack Iby chemical agents contemplated. The elongated tubular body of the device of Fig. 2 is indicated as an entirety by 2I and comprises an elongated tubular plastic shell 22 that is normally closed at its top by a displaceable plastic cap 23, equipped with a suit--Y able bail 24. No special means has been shown for detachably anchoring the cap 23 to the tubu- When made of metal, itis desirable toy make all metallic parts of the same metal, since the chemical 2,4-D and some other weed destroylar shell 22, but this may be accomplished fby any suitable means, such as; friction nt, screw threads, bayonet pins and slots, or other wellknown means, allowing removal of the cap 23 lfor filling of the reservoir space 25 provided by the bore of shell section 22. The lower end of the tubular shell section 22 is closed by a supplemental shell section 26, which may also be of suitable plastic material and may be assumed to be permanently secured in telescopic engagement with shell section 22 by suitable cement or the like at 21. Disposed in the lower portion of shell section 22 is an inverted cup-like element 28, which serves as a base of reaction or seat for a coil compression spring 23 and is provided with a relatively7 large axial passage 30. The axial bore 3| of the supplemental shell section 26 provides a pump cylinder. The closed outer end of shell section 25 is provided with an axial plunger bore 32 of greatly reduced diameter with respect to that of the cylinder bore 3|. Working slidably through this plunger bore 32 is a Iplunger 33, which may be made of any suitable material, but will preferably be metallic and may be assumed to be of aluminum. The plunger 33 is provided at its inner end with a xed head serving as a piston 34. In this form of the invention, there are no special passages, such as shown at I5 in Fig. 1, through the piston. However, suitable flow communication between the upper and lower sides of the piston 34, during relative upward retracting movements of the said piston 34, is provided by a somewhat increased clearance between the perimeter of piston 34 and the inner surface of cylinder 3l. The [piston 34 is yieldingly urged or biased toward its intended position of Fig. 2 by the compression spring 29, which is interposed therebetween and the inverted cup-shaped element 28.

In the form of the invention shown in Fig. 2, a resilient valve element or seal 35 is provided and which is similar to the valve element I6 of Fig. l and is likewise anchored fast on the plunger 33 and lies flat against the undersurface of piston 34. To allow discharge of fluid from the cylinder 3 E, we reduce the diameter of the upper portion of plunger 33, with respect to the plunger bore 32, so as to provide an annular iiow passage 36 which communicates with a circumferentiallyspaced series of downwardly and outwardly directed final discharge orices or passages 31, which produce a spray pattern corresponding to the spray pattern produced by discharge through the orifices l@ of Fig. 1. In Fig. 2, the reduced diameter portion of the plunger 33, defining the inner wall of annular passage 36, is indicated by 33 and terminates at its lower end in a shoulder 39 joining the same to the maximum diameter portion of the plunger 33. In the arrangement of Fig. 2, upward charging movements of the piston 34 and plunger 33 are limited by engagement' of piston 34 with a stop shoulder 40; the design being such that the inner ends of the final discharge passages 31 will Ibe covered and closed by the maximum diameter portion of the plunger 33 when the piston is in its said upper extreme position against stop shoulder 40, so as to prevent downward discharge of fluid when the piston is in its said upper position.

Operation of Fig. 2

The manner of operation of the device of Fig. 2 is identical to that described in connection with Fig. l, insofar as handling by the operator is concerned. However, when the piston 34 of Fig.

6v 2 partakes of relative upward movement with respect to the tubular body 2l, the flow of fluid from the space above to the space below the piston 34 will be around, rather than through, the piston 34 and will be suiiciently rapid to completely fill the space below the piston 34 under normal relatively slow upwardmovements of the piston 34 under manual pressure. However,

when manual pressure is released, the spring 29 will take over and move the piston 34 downwardly with suicient speed to fproduce ample discharge pressure below the piston 34, even in the presence of considerable backow through the generally annular flow passage clearance 38 between the piston 34 and cylinder bore 3l. In other words, the pump will be designed to produce the desired volumetric discharge through passages 36 and 31 in the @pressure of the predetermined backiiow past piston 34. During return strokes of the piston 34 under the action of spring 29, iiuid will be discharged from orices 31 onto the leaves of the oifending plant or weed exactly as described in connection with Fig. 1. Of course, when the piston 34 reaches the bottom of its stroke, the valve element or seal 35 will be compressed between the piston 34 and the closed end of shell element 26 and will positively cut off flow through the annular passage 36 and circumferentiallyspaced discharge passages 31.

Our invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the objectives set forth; and while we have shown a commercial embodiment y of our improved device it will be understood that the same is capable of modication without departure from the scope and spirit of the invention as dened in the claims.

What we claim is:

1. In a device of the class described, an elongated tubular body having closed upper and lower ends, the lower end portion of said tubular body affording a pump cylinder, that portion of the tubular body above said pump cylinder dening a liquid reservoir which is in communication with said pump cylinder, an axial plunger bore through the closed end of the tubular body which is of reduced diameter with respect to the pump cylinder, a plunger working slidably through said reduced diameter bore, a pump piston having a restricted ilow passage therethrough secured on the inner end of said plunger and working slidably in said pump cylinder bore and being of enlarged diameter with respect to said plunger, yielding means urging the piston toward the lclosed end of the pump cylinder, a resilient annular valve fixedly carried by the plunger adjacent the lower end of said piston and immediately underlying but free of the lower end of the restricted flow passage and normally covering said passage, said resilient valve element being normally compressed between the piston and the closed end of the cylinder by said yielding means and then serving to cut off ilow through or past said piston, said resilient valve element acting as a check valve under reciprocatory movements of the piston to allow flow through the piston bore during inward strokes and to close such passage during downward movements of the piston, and a generally downwardly directed discharge passage from the space below the resilient valve element.

2. In a device of the class described, an elongated tubular body having closed upper and lower ends, the lower end portion of said tubular body aording a pump cylinder, that portion of the tubular body above said pump cylinder defining a liquid reservoir which is in communication with said pump cylinder, an axial plunger bore through the closed end of the tubular body which is of reduced diameter with respect to the pump cylinder, a plunger working slidably through said reduced diameter bore, a pump piston having a restricted ow passage therethrough secured on the inner end of said plunger and working slidably in Vsaid. pump cylinder bore and being'of enlarged diameter with respect to said plunger, yielding means urging the piston toward the closed end of the pump cylinder, a resilient annular Valve xedly carried by the plunger adjacent the lower end of said piston and immediately underlying'but free of the lower end of the restricted flow passagev and normally coveringsaid passage, said resilient valve element being normally compressed between the piston and the closed end of the cylinder by said yielding means and then serving to cut off flow through or past said piston, said resilient valve element acting as a check valve under reciprocatory movementsof the piston yto allow ow through the piston bore during inward strokes of the piston and to close such passage during downward movements of the piston, and a restricted discharge passage through said plunger from a plane immediately below the resilient valve element to atmosphere at a plane below the closed end of the cylinder.

3. In a device of the class described, an elongated tubular body having closed upper and lower ends, the lower endfportion of said tubular body affording a pump cylinder, that portion of the tubular body above said pump cylinder defining a liquid reservoir which is in `communication with said pump cylinder, an axial plunger bore through the closed end of the tubular body which is of vreduced diameter with respect to the pump cylinder, a plunger working slidably through said reduced diameter bore, a pump piston fast on the inner end of said plunger and working slidably in said pump cylinder bore and being of enlarged diameter with respect to said plunger, yielding means urging the piston toward the closed end of the pump cylinder, a restricted flow passage between the pump cylinder spaces above and below the piston. and a resilient annular valve rseal interposed between the piston f and the closed lower end of the tubular body against which the piston is normally seated under the action of the yielding means, ra generally downwardly directed discharge passage from the cylindrical space below the piston to atmosphere and which is operatively lassociated. with said piston and valve seal, said piston serving in cooperation with the resilient valve seal to close oil communication between said pump cylinder and the discharge passage, said restricted flow passage between the cylinder spaces labove and below the piston being defined rby a bore through the pis- 8' ton and located radially outwardly 'of the' plunger, said generally downwardly directed discharge passage from the cylinder space Vbelow the piston being formed in the plunger, thelower discharge end of said discharge passage opening through the side of the plunger and being disy posed in such downwardly spaced relation to the piston that it will be below the plunger bore when the piston and plunger are extended, but will be withdrawn within the plunger bore and closed when theA piston and plunger are in their upper and retracted positions.

4. In a device of the class described, an elongated tubular body having closed upper and lower ends, the lower end portion of said tubular body affording a pump cylinder, that portion of the tubular body above said pump cylinder dening a liquid reservoir which is in communication with said pump cylinder, an axial plunger bore through the closed end of the tubular body which is of reduced diameter with respect to the pump cylinder, a plunger working slidably through said reduced diameter bore, a pump piston fast on theinner end of said plunger and working slidably in said pump cylinder bore and being of enlarged diameter with lrespect to said plunger, yielding means urging the piston toward `the closed end of the pump cylinder, a restricted ilow passage between the pump cylinder spaces above and below the piston, and a resilient annular valve seal interposed between the piston and the closed lower end lof the tubular body against which the piston is normally seated under the action of the yielding means, a generally downwardly directed discharge passage from the cylindrical space below the piston to atmosphere and which is operatively associated with said piston and valve seal, said piston serving in cooperation with the resilient valve seal to 'close orf communication between said pump cylinder and the discharge passage, said generally downwardly directed discharge passage froml the cylinder space below the piston being formed in the plunger, the lower discharge end of said 1discharge passage opening through the side of the plunger and being disposed in such downwardly spaced relationto the piston that it will be below the plunger bore when the piston and plunger are extended, but will be withdrawn within the plunger bore and closed when the piston and plunger are in their upper and retracted positions.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,046,408 Voges Dec. 3, 1912 1,264,554 Peron Apr. 30, 1918 1,274,915 McEnery Aug. 6, 1918 1,334,769 McClain Mar. 23, 1920 2,125,572 Johnston Aug. 2, 1938 

